1. business and industrial
2. construction

Journal of Renewable Natural Resources Bhutan
ISSN: 1608-4330
Assessment of Seismic Behavior of Light Steel Frames (LSF) with
use by Nonlinear Static Ana Assessment of Seismic Behavior of
Light Steel Frames (LSF) with use by Nonlinear Static Analysis
Mohsen Vallipour , Dr.Fereydoon Omidinasab*
Department of Civil Engineering, College of Civil, Khomein Branch, Islamic Azad University
Khomein, Iran,
*Corresponding Author
ABSTRACT:
The lightweight steel framing system which is abbreviated as LSF is a building system applied
for the construction of up- to -5 floor buildings which is approved by development and civil
engineers in modern and developed countries. This system which has a lot of similarity to the
construction method of wooden buildings is formed based on application of such parts as stud
or mullion (or soldier beam) and track or runner, and main structure of the building is made up
of the combination of cold-rolled galvanized steel profiles. The sections used in this system are
C, U and Z, which are connected together by cold joints. Each wall is made up of some of the Cshaped (stud) parts which are bound to drain pipe horizontal parts shaped like U or C in upper
and lower level. This system is mostly implemented applying light ceiling and in some cases
along with different kinds of ceilings. The beams and joists of these kinds of light ceilings are
similar to studs and tracks of the wall. The final ceiling is normally kind of steep and is
considered using metal trusses made of cold-roll profiles. Other parts of the building are
implemented using cold-roll profile and are covered using different coatings such as gypsum,
cement and wooden boards etc. this system is widely used for about 20 years and as an
alternative to the traditional methods of construction won a better status in the construction
industry of developed countries. This system is applied in different constructions such as office
and housing buildings, hotels and hotel-apartments, school and academic buildings, restaurants.
Findings suggest that not only does it at least double the pace of implementation but it also
reduce the steel consumption up to 40 percent. The great deal of advantages of this system such
as high speed and quality and proper seismic function has been remarkably attracted the
attention of developers and engineers around the world, it has also the ability to be mixed with
other structural systems as well. In this study, seismic behavior of system (LSF) irregular
structure is examined. In this study a system of cold formed steel frame bracing for the first time
this idea has been discussed.
Keywords: lightweight steel framing (LSF), cold-rolled sections, Irregular Structures, Numerical
Method
Introduction
Iran is one of the most seismic areas in past years the earthquake-prone world Large and has
experienced devastating. The need for earthquake resistant structures and style, something that
demands attention and widespread owners and engineers. One of the structures Lightweight with
high resistance to earthquakes in recent years, largely in the industrial production of
building Administrative, commercial and residential systems have been used LSF Cold rolled
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Mohsen Vallipour , Dr.Fereydoon Omidinasab
steel sections that (CFS) is generated. The method in developing countries as an alternative to
traditional methods of construction, and its widespread use has been provided.
Light steel frame construction system (Lightweight Steel Framing) briefly LSF it is called, is
a building system for the construction of Mostly short time and the time (up to 5 Class) is
used and
from
system
approved civil
engineers
in
developing
countries And
modern. Application This building andto title one system instruments independent, mostly At Ma
ss building Building Two Category And Building the Business Small, Units Industrial and Hall
the athletic one Category.To Construction Sections Cold Carriage By Matching Regulations Lett
er The Related To This Structures Use From Bug Different Allowed Is.Components Upright This
System To Title Member Porter Columnar At Loads Gravity Action To The, Some From This U
sers That Crater AnchorageLateral Ray
structures
are In
addition, On Load Gravity, Bearing Forces From Loads Lateral Also To That the members of
the force (stud) in the system Structures This Building organized from Joist Cold rolled steel
joists
that
distances With Attention to Level Bearing
Capacity
of
and dimension Parts Cover Ceiling That To be board The Wood, Cement or Dahl Concrete Arme
d Is, Determination being present industry
building Building Iran Use Film Mouths Anchorage by with Users Diameter to Buildings
until Four residential
floor allowed.
Profiles Cold ByResistance Slightly at Equal Fire are and should to Good Protection Are. One Fr
om Reasons Application Plaster to Title Cover Internal This Systems
Access To This Target.
The use of galvanized steel, the stability of the system against weathering and micro-organisms
has increased. From an environmental point of view, this building is one of the components to
build systems that little energy is consumed. The weaknesses of the system, if it is not running
all the technicalities regarding the risk of contracting and expanding sound modes. The system is
lightweight construction (about 60% by weight of the construction unit of conventional systems)
makes the force applied in the event of an earthquake is significantly lower than conventional
buildings, so that in most cases effect of forces exerted by the wind more and determines the
balance is due to the earthquake. In addition, low weight makes it a good choice for areas with
low soil strength, should be considered [1-3].
1.
Principles and methods of design and implementation of structural
A) The introduction of lightweight steel frame (LSF)
Light steel structure (LSF) Building a new system for the implementation of the 5-storey
building with a floor limit is commonly used and approved systems for civil engineers in
developing countries and modern. The structure of rolled steel sheet to ensure the sustainability
of the building, Sheets and gypsum board as the inner lining and the outer wall of the facade is
made up of parts. This system has the ability to combine with other systems is structural. This
system reduces the weight of the structure to fifty percent of the biggest points against
earthquake. Cold-rolled steel members used in the building of the 1850s began. However, in
America until the publication of the first edition of these sections of the building regulations of
the American Association of Steel in 1946 (AISI) Found a large spread. This system is similar to
the construction of wooden buildings, according to the name of the application components
(Stud) or make the track (Track) or runner is formed from the combination of cold rolled
galvanized steel profiles, the main structure of the building is erected. Sections used in this
system, U, C, Z, usually with cold joints are connected to each other. Thin-wall steel, galvanized
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steel sheets are used to cold rolling and using Roll Forming are shaping the industry. According
to the regulations set for rolled steel sections style base metal thickness (the thickness of the
metal without protective coating) between 455 ¸ 0 mm to 3 mm has been developed. These
sections will be cutting production plant, the production levels of high-quality and uniform in
size and speed to be essential. Placement of the steel sections within walking distance to the
bearing walls creates the appropriate strength and stiffness against lateral loads due to wind and
earthquake.
B) Introduction of structural components and connectors
Structural connectivity LSF The foundation by a horizontal coil of cold rolled profile
section C Formed, in Figure 3-1, the members and how this connection is shown in detail in
connection connectivity components LSF The foam is also used in class,
Figure (3-1) Connection Details LSF structure of reinforced concrete foundation and floor
The vertical component of the system as a member of the gravity load bearing column in the act,
some of the members of the crater side braced structures are in addition to gravity loads, lateral
loads due to wind forces sustained also become members under the name (Stud) in the optimal
distance is 66 cm acetate system are introduced and connected to the coil members Stud Column
Floor Runner by a screw element carried by-section. In Figure (3-2) is an example of a member
of Stud and how to connect it as shown.
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Figure (3-2) of the coupling member stud
In Figure (3-3) how to connect a member of the bar ceiling columns Stud who mediated by
members of the C-section as shown orthogonal Frack and perpendicular to the beam ceiling,
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Figure (3-3) how to connect a member of the bar ceiling columns Stud
Figure (3-4) Stud columnar member of a class
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Stud columns in braced by placing members of the members from the other members Stud
distinctive looks and functions the way it should be carefully and pay special attention in the
number (3-5) the way construction sections Details of connecting these members to braces and
horizontal coils used in high-class shows.
Figure (3-5) Members column Stud located in braced
In figure number (3-6) and (3-7) Members noted that the images of horizontal bending and act as
a member of the beam and joist to beam connection details shown remarkable the holes created
in the lives of bending and bar members of cross sections, including paths are installations.
Figure (3-6) picture of the main roof beam flexural members
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Figure (3-7) beam to beam connection details Home
For embedding vertical openings in the walls of the system of horseshoe steal the same time and
sections of the column will be used for all connections by takes stud. Error number (3-8) and (3,
9) is an example of vertical as doors, windows, and members of the second degree requirements
are shown.
Figure (3-8) Details of opening the door on the vertical wall
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Figure (3-9) details in a popup window vertical wall
Since the main beams on a column of Stud Are, therefore, to establish design building the
system, the characteristics of the beam is used indiscriminately. In Figure (3-10) finally not
shown it. [5-10]
Figure (3-10) as an example of creating the crest of the LSF system
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2. Modeling and Analysis Models
Frame model of the application of a three-storey frame and a frame which is a five-story frame
model first class commercial, residential first and second respectively. Ground floor height of 3.7
m, 3.2 m height of the first floor and second floor of 2.5 meters. Stud spacing equal to 74 cm
center to center and columns as well as cold rolled two studs 12 which is based on sections 612
defined in the publication of management and planning, and also the information contained in
SAP software fully described below, using the software ETABS model takes the output of the
application to determine the irregular frame is controlled in accordance with paragraph 4-17. The
second model is a five-story frame with Sat characteristics (Table 4-6) and (4-9).
Frames irregular nonlinear static analysis method.
In this chapter frames designed with the software ETABS, using Abaqus software modeling and
analysis, and before the publication of this work 360 Management Planning, nonlinear static
analysis, nonlinear material behavior and we look at a height function and purpose of the shift is
calculated.
Nonlinear static analysis
Lateral load From Earthquake, Static and to Quantization to Form Increasing to Structures
Apply to
until There That Relocate at OnePoint the Specific (Point the Control) Under Effect Barjanby,
To Amount Certain (Relocate Target) Matching Relation to reach 1-1 or structures.
Deformation and Forces Internal Result from Analysis Static Nonlinear Should
with Criteria Admission In the same paragraph review The Place.
𝑇2
𝛿𝑡 = 𝐶0 𝐶1 𝐶2 𝐶3 𝑆𝑎 𝑒2
(1-1)
4𝜋
This relationship is the fundamental period of the building. The coefficient of correlation
correction to the spectral shift to shift a degree of freedom systems, roofing systems, multidegree of freedom is equal to one of the following values is selected,
-factor Participation in the first mode
- Approximate values in Table (2-1)
Other buildings
Any distribution
of the load
0.1
2/1
3.1
4/1
5.1
Table (2-1) Approx𝐶𝑜 .
Shear Buildings
The first type of
distribution in
Uniform load
accordance with
distribution
paragraph 5.2.
0.1
0.1
1.15
2/1
2/1
2/1
2/1
3.1
2/1
3.1
68
Building Floors
1
2
3
5
10 and more
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The coefficient is calculated as follows:
𝑇𝑒 ≥ 𝑇𝑠 → 𝐶1=0/1
𝑇
0.1+[𝑅−1] 𝑠
𝑇𝑒
𝑅
= 𝐶1 𝑇𝑠→ 𝑇𝑒<
In any case the amount shall not be less than 1 and greater than 5.1 will be available. The relation
R is the resistance of the following:
𝑆
R=𝑉 𝑎 𝐶𝑚
𝑦/𝑊
The relationship between spectral acceleration for the effective period of the first mode is the
effective mass coefficient for steel frames in buildings of three stories or more is equal to 9/0.
Multiplier effect of reducing the hardness and strength of the structural shift due to the inelastic
behavior and its value using the following table (2.2) is determined.
Table (2-2) coefficient values
T
The desired level of
performance
Frame Type
Uninterrupted use
0.1
Johnny Safety
3.1
Breakdown
threshold
5.1
T
Bodies of
two
0.1
0.1
Frame Type
0.1
1.1
Bodies of two
0.1
0.1
0.1
2/1
0.1
The table frame consists of a structural system in which more than 30% of the lateral load
carrying members that when the earthquake reduced the hardness of and resistance. Ordinary
moment frame, with the axis bracing frame, frames with semi-rigid connections, lean frame with
braces that are designed to stretch, non-reinforced masonry walls and walls of non-ductile shear
these are. Other structures of the two systems are considered. T values between 1.0 and Ts the
value is calculated using linear interpolation. After submitting a difficult factor for structures that
are positive (∝> 𝑜) = 1 and for structures which are then submitted to a negative stiffness (∝<
𝑜) can be calculated from equation 5-4. (𝐶3=1 )
𝐶3=1/0+|∝|[𝑅−1]1.5 (2-2)
𝑇𝑠
Time frequency main effective along case Check Based
on Model Behavior Two Linear Equal is with:
𝐾
𝑇𝑒 = 𝑇𝑖 √𝐾𝑖 (3-2)
𝑒
Where the fundamental period of the building, assuming elastic behavior is linear and lateral
stiffness. In addition, non-linear static analysis can be performed and simple method is perfect,
1At Method Full, Members Main And Ghyrasly At Model Login By And Behavior Nonlinear It
And Until Limit Possible Close To Reality Selected To. Also
Effects Lowering Login Calculation.
2- At Method Simple By, Only Members Main Model to There.
Behavior Nonlinear Members Main by Model Two Linear Similar Building to and Effects
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Mohsen Vallipour , Dr.Fereydoon Omidinasab
Lowering Spend View.
Number Slightly From Members Main By This Criterion Accepted Otherwise, To Power It And
To At Category The MembersGhyrasly Assumption And From Model Be
removed. At Analysis Static Nonlinearity, Center Crime Roof To Title Point The Control Reloca
te StructuresSelection To Be. Lateral load distribution on the structure should be similar to what
is possible when an earthquake will occur, and the critical deformation and internal forces in the
members Manager. There are three types of load distribution, which include:
1.1 Distribution Static linear proportional to the lateral load distribution, the distribution can be
used when at least 75% of the mass of the structure in the first vibration mode participate in the
desired direction. If you choose this distribution, a uniform distribution of the second type must
be selected.
1-2 proportional distribution of the first mode of vibration in the desired direction, the
distribution can be used when at least 75% of the mass of the structure of the mode of
participation.
1-3 linear dynamic analysis of the spectral distribution proportional to lateral forces, for the
purpose of investigating the vibrational modes must be selected such that at least 90% of the
mass of the structure of the partnership.
The lateral distribution of the second type must be one of the following methods to calculate and
apply the structural model.
2.1 A uniform distribution of the lateral load is proportional to the weight of each class is
calculated.
2.2 Distribution of the lateral load varies depending on the nonlinear structural model at each
step rise time using a valid method of changing.
Lateral load that can be selected in order to separate the positive and negative sides of the
structures and the relationship between the foundation of cutting change the location of each
step, point controlled to the side to change the location increase the 5.1 at the In nonlinear
analysis of target location registration Members gravity loads combined with lateral load shall be
proposed.
𝑄𝐺= [𝑄𝐷 +𝑄𝐿 ]
𝑄𝐺= 𝑄𝐺= 0.9𝑄𝐷
Dead load and live load effective in this regard, based on 519 standard and limit the effects of
gravity and lateral load of gravity of the load combination.
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Nonlinear behavior of structures that cut the connection between the base and the shift point
control according to the form (2-1) specifies the purpose of calculating the effective lateral
stiffness and effectively cut the surrender to the behavior of linear replace it with. To simplify
the nonlinear behavior, Point B should be selected such that the area under the curve of the linear
model the nonlinear behavior as well as the length of the line segment AD is equal to AB 6/0. In
that case, the relevant point B, section 6.0 give effective and cutting the base curve nonlinear
behavior, secant modulus represents the effective lateral stiffness. The simplified model of care
must be larger than the maximum base shear curve is non-linear behavior. The structures which
are then submitted to a barely positive (o <α) behavioral model in Figure (a) and the structures
which are then submitted to a negative stiffness (o<α) behavioral model in Figure (b) is.
Figure (2-1) curve Simple by the Force - displacement
3. Calculate the amount of displacement of the target three-storey frame, calculate the oscillation
period in seconds
𝑇 =∝ 𝐻3/4 (3-1)
In the above equation H The building height in meters and the building structural system of steel
moment frame buildings is equal to 0.08. Building height of 9.5 meters, in which case the period
of the structure is obtained 44/0. Effective period of the structure is equal to 6.0. The Iranian
Earthquake Resistant Design of Buildings Regulations (2800) (Third Edition) S a 5.1 Factors to
be considered C 0 And C 1 And C 2 And C 3 Respectively 2/1 and 1 and 2/1 and 1. We can then
shift the purpose of the study to obtain 195/0 M that it is applied in the analysis of the maximum
displacement of 200 mm on the model back.
As mentioned in the analysis of non-linear stress-strain curve of the material when the wall was
crashed into the plastic range begins. After loading the reaction force generated by the loading
structure of the software, and entered the output of Graph drawing is capped overs.
After applying the displacement of the anchor reaction force output from the model that the rest
of the form (1.3) Load displacement curve is studied.
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60
Load (KN)
50
40
30
M1
20
10
0
0
20
40
60
80
100
120
140
160
180
200
Displacement(mm)
Figure (3-1) curves of force - displacement
As shown in Figure (3-1) can be seen through the displacement of 50 mm Tilt reduced force
structure which indicates that the failure to increase the displacement of the structure
began. Swing at the load-displacement curve can be created and modified in a tough frame
buckling the professor explained, before buckling of the steel plates deform and force the
reaction been on the rise with steep although of Buckling still rising force that reflects the fact
that the buckling strength of the frame is created, but the increased displacement and reduced
energy absorption profiles generated power in the backrest is also reduced. Also, due to
structural failure after moving to the standard dimensions of structural guessed right and is
optimized. 200 mm removable canopy frame for frame base shear force is 48 kN. Moving in
class diagram in Figure (3-2) is remarkable.
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Figure (3-2) overall displacement classes
Navigate to 20 cm on the top floor and the first floor and ground coordinates are 14 and 8 cm. By
examining the form (3.3) is considered to be the most moving relative to the ground floor and the
first floor is the lowest relative displacement.
Figure (3-3) classes relative displacement (drift)
Calculate the target location using the equations to calculate the oscillation period in seconds,
H the height in meters of buildings and building systems, building structural steel bracing frame
is equal to 0.08. 5.17 meters is the height of the building, in which case the periodicity of the
structure is obtained 68/0. 84/0 is the effective period of the structure. The Iranian Earthquake
Resistant Design of Buildings Regulations (2800) (Third Edition) S a 5.1 is considered to be the
coefficients C 0 and C 1 and C 2 and C 3 and 1 and 2/1 respectively 1 And 1 is the amount of shift
in the purpose of the study is obtained from 322/0 m that henceforth the maximum displacement
of 325 mm is applied to the models.
4. The results of other models
Then load the other models have been done and the results are compared with each other.
Table (4-1) studied models
Model Name
M1
M2
M3
M4
Type variable
Thickness
Thickness
Thickness
Thickness
Thickness (mm)
0.8
1
1.25
1.5
73
Master's distance
(mm)
740
740
740
740
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Between master
and
Between master
and
Between master
and
M5
M6
Load (KN)
M7
Mohsen Vallipour , Dr.Fereydoon Omidinasab
1
610
1
700
1
780
100
90
80
70
60
50
40
30
20
10
0
M1
M2
M3
M4
M5
M6
M7
0
50
100
150
200
Displacement(mm)
Figure (4-1) force-displacement curve models studied
As the form (4-1) is visible in the model M4 is the greatest force tolerance the thickness of 1.5
mm is used, the maximum force of 93 KN tolerance in this model is equivalent to the model
M1 thickness of 0.8 mm with a maximum force of 48 KN which is an increase of almost 94%
show. The professor is also considerably reduce the gap distance of 800 mm to 610 mm master
strength is increased 130 percent. Also check to see that all models
after From Submission with Difficulty Are positive.
That is hardly a model with a steep increase in the yield point after the loss and damage potential
entered
The model is hardly reduced rate but still positive value, the value is positive, indicating that the
increase moving up to the maximum displacement of the target not only strength, but it does not
decrease the cutting forces with a smaller slope are still rising.
5. Software modeling in Abaqus
The software Abaqus for modeling profiles, bars, where the bar was totally and there are two
solutions, the first model of the rod element is Solid, Solid element diameter and dimensions are
exactly equal to the base model, but Runner master and is used to model the wire, solid or shell,
although it can also be used, but since the wire is modeled as a two-node and Orientation beams
and columns must be done carefully and solving complex relations greatly increased
computational cost is reduced and the accuracy of the results.
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To investigate the structural behavior LSF first review the plan and design of ETABS model is
selected. STUD AND RUNNER for modeling the element wire is used in the internal section is
determined so that a C-shaped cross section as shown in Figure (5: 1) defines the element wire is
attributed
to the
effects
of nonlinear from From Cut high under load side To Form Closer At View . Wire
Dougré
element
type
and
the Between Elements
Available at Abaqus
program
for modeling columns And Beams Selection.
This is done to reduce the computational mesh and the lower cost. The structural model and
corresponding cross-sectional profile is obtained.
Figure (5: 1) cross-sectional profiles obtained
For modeling side wall profiles are as follows.
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Figure (5, 2) the size of the frame rate of the studied
Abaqus software modeling can be done as follows.
Figure (5: 3) profiles modeled in Abaqus
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Figure (5: 4) frame model in Abaqus
Figure (5, 6) the load side of the frame
Barjanby is loaded into the top corner of the building on which it is applied.
Handling practices are starting from scratch and will continue to limit, in accordance with
Regulations FEMA302 Allowed to move relative to the structural steel frame structure height
equal to 2% is recommended, In this analysis, the failure to reach a height of more than 2% of
the frame, the movement is applied and the results reviewed.
Table (5: 1) the relative displacement prescribed in the bylaws FEMA302
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As mentioned in the analysis of non-linear stress-strain curve of the material when the wall was
crashed into the plastic range begins.
6. The 3-storey building model structure has been applied to the structural behavior is observed
in the displacement h 02/0 then based on the results can be seen that the brace system meets the
recommended maximum allowable displacement of the Regulations is FEMA302
Static analysis based on the standard frame rate of displacement applied for FEMA whose value
is equal to h 02/0. The 3-storey building with a height of 4.9 meters per floor for the amount
equal to 18 cm. In the next step of the analysis system has been applied load.
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Figure (6-1) displacement contour model
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Figure (6-2) Stress Contour Model
Figure (6-3) LSF frame model in Abaqus
Runner stress and maximum junction professor is expected to be the most susceptible to injury.
7 - Plastic joints
Joints of plastic essentially factor for waste Energy Been That Energy from Earthquake to
from By
means of plastic fittings, rigid die out. Theperiod and Length Plastic
hinge of
a Member Parametric Important at
Evaluation
Reply
and
Damage
Structures
under Earthquake Considered.
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Although
the methods are
different To Calculation Length Detailed plastic
and capacity of inelastic Recommended By, But No adjustment and
adaptation
of on the characteristic The Behavior of inelastic structures Existence. Further investigate the
force displacement curve as well as the shapes and contours of the model can be found in the
tabular overview of the model.
Suppose you That Bar The
national figure
(6-3) with Difficulty EI
constant
and detailed plastic, beginning at relying sometimes formed it. In
that case,
the Species That at Figure (7 -1) significantly to the amount of plastic hinge Case Demand on
Time to Power with Use from Theorems anchor surface, To Form Under stated that:
L
WL2
θdp = θ′p − θ"p = 2EI ( 12 − Mu )
(7-1)
That E Modulus Elasticity and I Moment of inertia.
Also Era Detailed Plastic One Section Critical to That Entitled Capacity RotationalAvailable Ca
lled Is, May to Shape Wrote the following:
Figure (7-1) Show Period by Detailed plastic And Curvature
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Figure (7-2) Show deformation Bar
Direction determination level joint plastic reliance time with use from story Anchor After the
relocation of the models studied displacement diagram taken along Runner and plastic hinge
length is obtained. Then, in Figure (7-3) contour displacement model is remarkable.
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Figure (7-3) Contour plastic strain at the top of the frame Runner plastic hinge location
Figure (7-4) Contour plastic strain at the bottom of the frame Runner plastic hinge location
As is clear from the end of July, a sudden change in slope is the form (7-4) is obtained by
controlling the amount of stress the fact that the area is prone to damage and the formation of the
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plastic hinge. Runner on a track entitled length Path Defined output and shift the elements of the
software.
Jabjayy- curve can be obtained, for example, the height of the form (7-5) curve for the show.
0/01321
Displacement(m)
0/01316
0/01311
0/01306
0/01301
0/01296
0
0/5
1
1/5
2
2/5
3
3/5
4
Distance along direction
Diag (5: 5) displacement curve during Runner
As is clear in the beginning and end of which is a strong runner sudden slope change reflects the
fact that 0.1of the length of the beam plastic hinge formation is the beginning and the end.
Conclusion
In this section we have introduce some results from the paper
1.
Through displacement of 50 mm Tilt reduced force structure that indicates that by
increasing the displacement of the structure began to surrender.
2. Swing at the load-displacement curve can be created and modified in a tough frame
buckling the professor explained.
3. Before buckling frame deform and the reaction force caused by the steep rising,
however, after the buckling force is rising which indicates that the post-buckling strength
of the frame is created, but after increasing the displacement and reduced energy
absorption profiles generated power is reduced at the fulcrum.
4. Because the structure of the standard moving to the failure of the structural guessed right
and is optimized.
5. The relative displacement of the ground floor is the minimum displacement relative to the
first floor is a three-store frame.
6. The force is tolerated in model M4 thickness of 1.5 mm is used, the maximum tolerated
The model is equal to 93 kN To the model M1 with a maximum thickness of 0.8 mm at
48 kN force is increased by almost 94%.
7. In the distance is considerably reduced from master teachers from 800 mm to 610 mm is
increased to 130 percent strength.
Runner stress and maximum junction professor is expected to be the most susceptible to injury.
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Bhu.J.RNR. Vol 3.1, 60-85: 2015
Mohsen Vallipour , Dr.Fereydoon Omidinasab
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